Crash when switching to a vessel without a flight plan

[lpgagnon]

A fairly straightforward crash: have 2 vessels in flight near each other, create a flight plan on one, open the "Final orbit analysis" window, and press ] to switch to the other vessel.

    @   00007FFEED04640F  	google::LogMessageFatal::~LogMessageFatal [0x00007FFEED04640E+46]
    @   00007FFEA3322D50  	principia__ExternalVesselGetPosition [0x00007FFEA3322D4F+34271]
    @   00007FFEA3324DF6  	principia__FlightPlanGetCoastAnalysis [0x00007FFEA3324DF5+405]
    @   000001C95BD201B7  	(No symbol) [0x000001C95BD201B6]
F0506 14:39:52.042968 13344 interface_flight_plan.cpp:74] Check failed: vessel.has_flight_plan() 097fcb9b-9799-4aa6-b25e-ac953c62c174

100% reproducible, can provide journal if needed, but I'm guessing it won't be.

logs